I've been learning flute for the past year, and here's what I've found useful:

• cyberflute.com

• Nina Perlove on YouTube

• etudes by Anderson (24 Progressive Studies) and Gariboldi (here's the collection I have)

• The Wye Practice Books for the Flute in one volume - This is absolutely wonderful for learning how to play well. He talks about tone, intonation, technique, vibrato, double tonguing, etc. Definitely worth the price.

My practice is oriented in two directions: Celtic-style songs and techniques, and general classical style. I'm currently working on the Am Partita by Bach. The hardest thing for me about learning flute (I'm also a clarinet/sax player!) is the subtleties of embouchure, and playing in tune (which are related, I suppose).